Prince:Lab Equipment & Instruments Description

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Mass Spectrometry

UPLC - Eksigent nanoLC-Ultra-2D

Splitless, low-flow Ultra High Performance Liquid Chromatography (UPLC) provides state of the art chromatographic sample separation. Analytes from complex samples are resolved as solvents at extreme pressure flow across capillary columns packed with micro beads (1.5-1.7um). Two 10-port valves can be plumbed for multiple 2-dimensional chromatographic separation strategies.

Mass Spectrometer - LTQ-Orbitrap XL +ETD

Our instrument ("Mustang Sally") excels at high-throughput proteomic, lipidomic and metabolomic analysis. Bridging the UPLC separation is a sensitive nano-electrospray source (10um ID tip). The instrument itself can be thought of as three mass spectrometers working in concert. The linear ion trap (LTQ) ushers packets of ions into the orbitrap and performs collision induced dissociation (CID) on a near infinite series of ion fragments (MSn) besides serving as a high speed mass analyzer when needed. Using flouranthene free-radical ions generated in the backend GC-MS, the LTQ can also perform electron transfer dissociation (ETD) which can be used to 1) fragment larger, higher charge state ions and 2) to gently fragment peptides with post-translational modifications (PTMs) in order to determine exact PTM location. The orbitrap is the first fundamentally new mass analyzer in 30 years and yields near FTICR mass accuracy (0.5-2 ppm) and resolution but without the need for a superconducting magnet. Within a fairly broad range, its mass accuracy is sufficient to identify an analyte's atomic composition from its precursor mass alone. A high collision cell near the orbitrap gives the instrument a total of three different strategies for fragmenting ions to ensure confident identification. Altogether, (with less than 1% error in peptide identifications) well over 1000 proteins from a HEK293 cell lysate can be identified in 2.5 hours of analysis.